Head-rest



(No Model.

0. E. AKELEY 8c 0. G. JUNKERMANN. HEAD REsT.

Patented Mar. 24, 1896.

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BIA-In AN DR'CW E GRRHAM PHOTDUTMOYWASHIN $10M 6 UNITED STATES PATENT OFFICE.

I CARL E. AKELEY AND CHARLES G. JUNKERMANN, OF MILIVAUKEE, WISCONSIN.

H EAD-REST.

SPECIFICATION forming part of Letters Patent No. 556,952, dated March 24, 1896.

Application filed August 21, 1893. Serial No, 483,631. (No model.)

To all whom it may concern:

Be it known that we, CARL E. AKELEY and CHARLES G. J TINKERMANN, citizens of the United States, and residents of Milwaukee,

in the county of Milwaukee, and in the State of lVisconsin, have invented certain new and useful Improvements in Head-Rests; and we do hereby declare that the following is a full, clear, and exact description thereof.

Our invention has for its object to materially improve that class of head-rests especially employed in connection with dental and surgical chairs, one feature of our improvements consisting in a pair of pads that remain at fi'xed points of a support, but maybe positively adjusted by pivotal movement to vary the intervening space, and which will automatically conform. to the head of a patient recumbent in a chair provided with our device.

Another feature of our improvements is an operators arm-rest having a positive vertical adjustment at either side of the head-rest, but which is automatically adjustable to various angles and may be readily varied as to position in a horizontal direction.

In view of the foregoing our invention consists in certain peculiarities of construction and combination of parts hereinafter described with reference to the accompanying drawings and subsequently claimed.

In the drawings, Figure 1 represents a rear elevation of our complete device partly broken away and in section; Fig. 2, a plan view of the same partly in horizontal section; Fig. 3, a detail illustration of a pad that constitutes part of said device; Fig. 4, a detail hori- Zontal section illustrating a clamping mechanism embodied in our invention; Fig. 5, a detail transverse section on line 5 5 of Fig. 2, and Fig. 6 an end view of the operators armrest shown. in the first two figures.

Referring byletter to the drawings, we show an annular seat A and a pair of channel-arms B that radiate from the seat in opposite directions at obtuse angles, said seat and arms being preferably cast in one piece from suitable metal, and in practice this casting is connected to the back of a chair by any convenient means. Inasmuch as certain dental and surgical chairs have their backs provided with spherical sockets, we have shown a ball 0 dependingfrom, the center of our casting for engagement with such a socket to thereby form a flexible joint, but we prefer to have the ball detachable, in order to adapt said casting to various other ohair-connectin g devices, and therefore we show said ball as provided with a flanged shank I), held to the underside of the aforesaid casting by screws 0, this being a very simple means for accomplishing the desired result.

The channels in the arms B intercept the seat A, and a stud din the center of said seat engages a slot e in a lever-cam D, this cam being held against vertical displacement by means of a washer f and nut g on the stud.

As herein shown, the cam has a loose mortise-and-tenon connection with the inner ends of bars E that slide in the channel-arms B above specified, and consequently the movement of said bars is wholly controlled by that of the cam; but while this is the preferable construction and arrangement of parts it would be no departure from our invention to depend upon some other means for the movement of said bars in one direction of their travel.

The stud-and-slot connection of the main casting and cam compensates for possible wear on the inner ends of the bars E and also insures of both bars being acted upon when said cam is operated. The outer ends of the bars E are made wedge-shape and oppose corresponding faces h of blocks F, loose in the channel-arms B above specified, it being preferable to recess these blocks at their juncture with said bars.

Parallel to each of the loose blocks F is another block G, rigid in the relative channelarm, and both blocks in each pair are recessed to form a socket for a ball 5 at the lower end of a shank j depending from a padbase II, the latter and said shank being eccentric to each other in the preferred construction of our device in order to accomplish the result hereinafter specified.

A spiral spring I encircles each of the shanks j and connects the pad-base thereon with one of the adjacent blocks, it being preferable, as herein shown, to have saidspring joined to the loose one of said blocks, where'- by the latter is held against lift when the wedge-bars are operated.

The bases H being preferably of the form herein shown, they present four points of bearing at suitable intervals apart, and thus the pads J more readily conform to pressure of a head laid thereon, especially when the corners of these pads are provided with cushioned springs 70, the latter being arranged on disks m secured to plates at that form the bot toms of said pads and conform to the shape of said bases.

The ball-and-socket joints between the pad bases and the blocks in the channel-arms permit of a yield of the pads to pressure in any direction when the wedge-bars are retracted, and an adjustment thus eifected is maintained by an outward movement of said wedge-bars. The springs I act to return the pads to their normal position when the wedge-bars are retracted and pressure removed.

Because of the eccentric connection of the bases H with their shanks j we are enabled to vary the space that intervenes between the pads J by a pivotal adjustment of the latter, this being a feature of considerable importance and advantage in our device.

Each of the channel-arms B is shown as provided with guides a for the vertical shank portion 3 of an angular bracket held at various elevations by means of a set-screw If, and the head portion to of the bracket has a longitudinal slot 'u, as is best illustrated in Fig. 2.

A squared portion w of a pivot-rod L engages the bracket-slot, and a head :0 on the rod opposes the inner side of said bracket. Arranged on the rod to bear against the outer side of the bracket is a sleeve M, and the outer end of said rod has a screw-thread engagement with a thumb-nut N that may be run tight against the sleeve this thumb-nut being opposed by a spiral spring 1 seated in the recessed portion z of an upholstered and metal-bound block P that turns, freely on said sleeve. Therecessed portion of the block has lateral branches 2, at its outer end, and the dimensions of said block are such that these branches may be brought in and out of engagement with the wings of the thumb-nut N at the pleasure of the operator, for whom the aforesaid block forms an arm-rest.

The spring y operates to automatically hold the arm-rest against the bracket out of the way of the thumb-nut; but when it is desirable to change the position of said arm-rest longitudinally of said bracket the former is drawn out against the resistance of said spring and the lateral branches of its recess engaged with the wings of said thumb-nut, whereby the latter may be readily turned on the engaging-rod to unclamp the same. The rod being unclamped, it may be moved the desired distance in the bracket-slot and again clamped by a turn of the arm-rest against the thumb-nut, after which, upon the release of said arm-rest, the latter will be forced back by the spring to its normal position.

From the foregoing description it will be seen that the arm-rest has free pivotal movement for the purpose of automatically adj ust ing itself to various angles and that a positive vertical and horizontal adjustment may be had by varying the elevation of the bracket and changing the position of the rod that is clamped thereto. It is also to be observed that both head-rest pads are locked or unlocked by one movement of the lever-cam.

Having now described our invention, what we claim as new, and desire to secure by Letters Patent, is

1. Ahead-rest comprisinga support, clampsockets at fixed points on the support, ballshanks engaging the sockets, pads eccentrically connected to the shanks, and spiral springs surrounding the shanks intermediate of the sockets and pads, substantially as set forth.

2. Ahead-rest comprising a support, blocks arranged in pairs at fixed points on the support and recessed to form spherical sockets, one block in each pair being fast to said support and the other loose therein, wedge-bars in the aforesaid support operative against the loose blocks, a lever mechanism for operating the wedge-bars, ball shanks engaging the sockets, and pads connected to the shanks, substantially as set forth.

, 3. A head-rest comprising a supporting device in the form of an annular seat having divergent channel-arms provided with blocks arranged in pairs and recessed to form spherical sockets, at least one block in each pair being loose, pads having depending shanks terminating in balls that engage said sockets, sliding wedge-bars in the channel-arms opposed to the loose blocks, and a lever-cam arranged in the seat to oppose the wedge-bars,

/ substantially as set forth.

4. A head-rest comprising a supporting device in the form of an annular seat having divergent channel-arms provided with blocks arranged in pairs and recessed to form spherical sockets, at least one block in each pair being loose, pads having depending shanks terminating in balls that engage said sockets, sliding wedge-bars in the channel-arms opposed to the loose blocks, a stud rising from the seat, and a lever-cam that has a slotted engagement with the stud and opposes the wedge-bars, substantially as set forth.

5. A head-rest comprising a supporting device in the form of an annular seat having divergent channel-arms provided with blocks arranged in pairs and recessed to form spherical sockets, at least one block in each pair beng loose, pads having depending shanks termlnating in balls that engage said sockets,

sliding wedge-bars in the channel-arms opposed to the loose blocks, and a lever-cam that is arranged in the seat and has loose mortiseand-tenon connection with the wedge-bars, substantially as set forth.

6. A head-rest provided with a positive vertically-adjustable bracket having a horizontal longitudinallyslotted upperporti on, a rod that engages this slotted portion of the bracket and has a head opposed to the inner side of the same, a sleeve on the rod, a block 1o loose on the sleeve and provided with a recess having lateral branches at its outer end, a spiral spring seated in the block-recess, and a thumb-nut run on said rod in opposition to the spring, the block being of such dimensions as to normally clear the thumb-nut, substantially as set forth.

In testimony that We claim the foregoing We have hereunto set our hands, at Hilwaukee, in the county of Milwaukee and State of Visconsin, in the presence of two witnesses.

CARL E. AKELEY. CHARLES G. J UN KERMAN N.

l'Vitnesses:

N. E. OLIPHANT, H. G. UNDERWooD. 

